The specific etiology of a majority of cases of keratitis and uveitis, as well as the exact immunologic mechanism of corneal graft rejection is unknown. Yet these entities frequently cause significant visual loss and blindness. The purpose of the proposed project is to elucidate the effector mechanisms involved in the immunopathology of anterior segment ocular inflammation (including graft rejection) and to test experimentally the efficacy and side effects of new therapeutic approaches. These studies will deal with two major subjects: 1) the role of soluble mediators ("lymphokines") of cellular immunologic reactions in ocular inflammatory disease, and 2) the use of blocking antibody serum (BAS) in the prevetion of immunologic corneal graft rejections. Lymphokines will be produced by guinea pig lymph node cells and purified and characterized. The lymphokines will then be placed in contact with eye tissue both in vivo and in tissue culture. The ability of lymphokines to cause tissue injury in the presence or absence of inflammatory cells will be investigated. An antibody will be made to a purified lymphokine preparation and its ability to block or suppress lymphokine-mediated tissue damage will be evaluated. Guinea pig anti-rabbit lymphocyte serum will be prepared and modified chemically so that it will not bind complement. The characteristics of modified BAS and the mechanisms by which it protects corneal grafts from rejection will be studied by in vivo and in vitro studies.